Signal
Ethernet Controller (PHY / MAC)
Network interface ICs bridging digital data to twisted-pair copper.
What is it?
An Ethernet controller is either a PHY (Physical layer, copper or fiber line driver) or a MAC+PHY combo. The PHY handles the analog magic, magnetic coupling, line equalisation, auto-negotiation. The MAC handles framing, addressing, and bus interface (RGMII, MII, SGMII) to the host processor. Used in any device needing wired network connectivity, routers, switches, embedded systems, IoT gateways.
When do you need it?
- Adding 10/100/1000 Mbps Ethernet to a host SoC that has MII but no integrated PHY.
- Multi-port industrial switches (need multiple PHYs).
- Embedded gateways and IoT bridges.
- Energy-management and building-automation controllers (BACnet-IP over Ethernet).
How to pick the right one
- Speed
- 10 Mbps (legacy), 100 Mbps (common embedded), 1000 Mbps (consumer / industrial), 2.5/5/10 Gbps (server / datacenter).
- Host interface
- MII / RMII (10/100), GMII / RGMII / SGMII (Gigabit). Match to host MAC.
- PHY only or MAC+PHY
- PHY-only if host SoC has integrated MAC (most do). MAC+PHY for designs without MAC.
- PoE support
- Some PHYs integrate PoE-PD controllers; others need an external PD controller.
- Energy Efficient Ethernet (EEE)
- Supported in most modern PHYs, reduces power during idle.
- Operating temperature
- Industrial -40 to +85°C, automotive -40 to +125°C with AEC-Q100.
What Magnias offers
Magnias Ethernet controller portfolio covers 10/100 and 10/100/1000 PHYs for embedded / IoT / industrial applications, with consumer and AEC-Q100 automotive variants. Consult your FAE for the latest recommendation.
Common questions
Do I need magnetics?
Yes, Ethernet over copper needs isolation magnetics between PHY and the RJ45 connector. Many modern RJ45 jacks have integrated magnetics.
PHY vs MAC+PHY for an SoC project?
Most modern SoCs have integrated MAC, so a PHY-only chip is enough. Older SoCs without MAC need MAC+PHY combo IC.
How long can an Ethernet cable be?
Standard CAT5e/6 spec is 100 m per segment. Longer needs a switch in the middle, or fiber.